![s_s07_20121887.jpg](http://cdn.theatlantic.com/static/infocus/shuttle032812/s_s07_20121887.jpg)
United Space Alliance technicians secure several of space shuttle Endeavour's main propulsion system tanks after they were removed from the orbiter's mid-body, at NASA's Kennedy Space Center in Florida, on March 21, 2012. The tanks will be retained for possible future use on the agency's Space Launch System Program. (NASA/Dimitri Gerondidakis)